The question is does that heating oil have a “shelf life,” and what happens if you burn it once it has past its prime?
The good news is that standard heating oil will last about 18-24 months, which means there’s no need to worry if you don’t finish all your heating oil in your current heating season.
Older oil can still be used, too – it’s just won’t produce as much heat as new oil. However, you don’t really want to over-rely on this older oil if you want your furnace or boiler to function properly: if burning your older oil can’t meet your heating equipment’s minimum requirement for heat, it will shut off, and you’ll need to call for service to get it up and running again.
It’s also important to remember that 18-24 months is an average shelf life for heating oil: several factors can influence that number up or down, including:
Having quality heating oil helps, too – a big reason to get your heating oil deliveries from a reputable heating oil supplier rather than a fly-by-night discounter.
The bottom line: if you get your heating oil from a reputable oil supplier, maintain your heating oil tank, and aren’t waiting two years between heating oil deliveries, you should be fine.